Altering the Path of Evolution Current Reproductive Technologies and Genetic Engineering with the use of

Altering the Path of Evolution

Current Reproductive Technologies and Genetic

Engineering

with the use of

“Biotechnology is an area of applied science that has

grown at an astonishing rate over the last two decades. It promises to have a profound effect on our use of other organisms, our impact on the environment, our health,

and even on the nature and direction of our own evolution.”

Allan, R. (2000) Year 12 Biology 2001 – Student Resource and Activity Manual BIOZONE International Ltd.

Now and the Future•Today reproductive biotechnology and genetic engineering is advancing at a revolutionary pace. This speed makes it difficult for us to always see the bigger picture involving not only all of humanity, but all living things and their physical environments. All too often the focus is on immediate gains to a limited number of individuals.

•This PowerPoint will allow us to begin to understand how the application of biological theory and technology interacts within the world in which we live.

•Biologists of the present and future need to be more intelligent, responsible, analytical and forward thinking than ever before in order for the biological world to flourish, rather than suffer the consequences of poor biological decisions and actions.

Selective Breeding•For as long as humans have been agriculturists they have selected for favourable characteristics in the plants and animals by breeding desirable traits or characteristics together in similar varieties of organisms.

•In doing so, farmers, breeders and scientists have influenced the natural gene pool by changing it to suit their needs.

•Once a favourable organism has been bred for a particular purpose, it is reproduced continually. On the reverse hand, undesirable organisms are not bred. This begins to sound like a little like natural selection. Although it is selection, it is not ‘natural’. Actions such as these place focus on only a few types of organisms and their genetic characteristics, and therefore reduce the biodiversity in a community. Let’s take a look...

Artificial Insemination•Artificial insemination (AI) is the injection of male semen into either the vagina or cervix of a female without the act of sexual intercourse•The first record of AI dates back to an Arab chieftan in the 1320s who used this technique to produce superior horses. •Today most farmed animals are bred by AI.•Desired characteristics include: cattle with more beef, higher milk production, milk with more butter fat; or sheep with finer wool; or pigs with less fat.•Champion sheep, pigs, bulls or horses can have their sperm collected, frozen and then flown anywhere in the world in order to provided a desirable mate for a desirable female living in another paddock in another part of the world.

Artificial Inseminationhttp://www.equiworld.net/uk/horsecare/artificialinsemination/artificialinsemination.htm

Semen is collected from the stallion before he is able to penetrate the filly.

http://www.equitainer.com/

An advertisement for a sperm

transport container

Artificial Insemination•Overuse of the sperm from one male can reduce genetic diversity in the population. This becomes a problem if;

• the male is later found to carry a harmful recessive or late onset disorder that has now been spread throughout a large population. In case this should happen it is important to maintain detailed pedigrees in order to trace related animals.

•there is an environmental (physical or chemical) change and there is no genetic variety in order to allow the population to adapt effectively over time.

•Over use of a small number of breeding animals results in many consanguineous matings. When related individuals that are heterozygous for undesirable recessive traits breed, there is a 25% chance of that trait expressing itself in the phenotype.

Artificial Pollination

•Artificial pollination is the removal of the male pollen from one flower which is then deposited on the female stigma of another flower.

•As with AI, artificial pollination aims to breed organisms with the most desirable characteristics.

•Mendel used artificial pollination when conducting his pea experiments.

•Desired characteristics include higher yield, larger fruit, resistance to frost, resistance to disease.

Artificial Pollination

http://pro.corbis.com/search/searchFrame.asp

Artificial Pollination•Overuse of artificial pollination can reduce genetic diversity in the population. This becomes a problem if:

•there is an environmental (physical or chemical) change and there is no genetic variety in order to allow the population to adapt effectively over time.

•as the plants in use have similar genetic characteristics they are particularly susceptible to any disease they may come in contact with.

•In the early to mid1800s the Irish had so little land they all farmed potato – a crop with a high yield. When a few plants became infected with a fungus it wasn’t long before all crops were infected. As the Irish farmer had planted nothing else, mass starvation (over 1 of the 3 million inhabitants) was inevitable.

Cloning•A clone is an organism with an identical genotype to another. Cloning can produce an organism with the identical genetic make-up to the parent.

•Cloning occurs naturally in all organisms that reproduce asexually. When cells divide by mitosis they are cloning themselves.

•Humans have been cloning plants for thousands of years by simply taking cuttings from one plant and growing a new plant from it.

•Bacteria mostly reproduce asexually therefore cloning themselves. Some animals also clone themselves asexually. Examples include: budding in jellyfish and coral; fragmentation in some worms; and parthenogenesis – the ‘virgin birth’ in bees. (see ‘Asexual Reproduction’ PPT in Biology folder)

•Identical (maternal) twins are clones, but they are produced from 2 parents, neither of whom is their clone.

•Cloning of animals (that usually reproduce sexually) from one generation to the next is extremely difficult and has only recently been achieved due to the advance in reproductive technology.

1. Cloning plants – using cells from a singe parent

http://science.howstuffworks.com

Cells taken from root tip where

mitosis is actively taking place

Root cells are cultured (grown) in

a nutrient media that provides the

cells with everything they needin order to

grow and reproduce

Cells are isolated

Cells start to form

identical new plants

Offspring are clones of parent

2. Cloning Animal Cells– Using undifferentiated pluripotent stem cells from a single blastocyst

created by two parents

•After the sperm fertilizes the oocyte the single celled embryo undergoes cell division by mitosis. After several hours a blastocyst (bundle of cells) forms. It is possible to remove and isolate the undifferentiated stem cells from the centre of the blastocyst without destroying them or their function.

•Each isolated undifferentiated pluripotent stem cell will continue to divide into a normal organism – each one genetically identical.

•If the cells are separated too late then they have already begun to differentiate – that is, take on different roles within the function of the whole organism. The cells will not function properly in isolation once differentiated.

•This form of cloning has been used in agriculture.

•Let’s have a look at how this works…

Fertilization

Cell divides by

mitosis into 2 cells

Mitosis continues - 4 cell morula,

etc

Embryo forms

blastocyst

Central blastocyst cells

are undifferentiated

Central blastocyst cells are

dissociated

Cloned identical ‘twins’ are cultured in media and implanted as embryos into

females of the same species. Note: they are clones of each other, not of either of

their parents.

2. Cloning Animal Cells– Using undifferentiated pluripotent stem cells from a single blastocyst

created by both parents

3. Reproductive cloning of a single animal from differentiated somatic cells using Somatic Cell Nuclear Transfer (SCNT)

•When cloning a whole organism, instead of fusing two gametes (1N + 1N= 2 N) scientists take the nucleus of a somatic cell (2N) and place it in an oocyte that has had the nucleus removed (0N). This is known as somatic cell nuclear transfer (SCNT).

•The somatic cell is differentiated and it has only been in recent years that scientists have been able to reverse differentiation. Usually, skin cells only know how to act as skin cells, muscle cells are programmed to be muscle cells, and so on. Scientists have had to convince the skin cell or muscle cell to forget its role in order to become undifferentiated so that it can develop into a whole new organism composed of a variety of different cell types.

•For approximately every hundred attempts to clone a mammal, only 1 is successful. The embryos suffer an enormous variety of structural, behavioral and/or chemical abnormalities.


•To this day it is not clear what makes this complex process a success or failure. The method for cloning each organism is slightly different and the whole procedure is still highly experimental.

•Ian Wilmut and team at the Roslin Institute in Scotland reported the first cloned mammal in 1996.

•Since then scientists have been able to clone a variety of mammals including cows, cats, rats, rabbits, pigs, horses, oxes and goats.

•Serious attempts at cloning whole organisms by SCNT began about 40 years ago. John Gurdon had some success cloning frogs in 1970. The cloned frog developed only to the tadpole stage before it died, therefore never becoming an adult frog.


http://science.howstuffworks.com

Gurdon’s Experiments from the 1970s

Nucleus removed from oocyte

of frog A

Nucleus taken out of somatic cell of frog B and fused with enucleated oocyte from frog A

Tadpole cloned from frog B – dies before developing into adult frog


htt

p:/

/sci

ence

.how

stuff

work

s.co

m

Dolly with her

surrogate mother

•At two years of age Dolly gave birth after a normal conception & pregnancy

•RIP. Dolly died in 2003 due to a lung infection. She was only 6 years old – half the age of the average sheep.

•Is this ‘experiment’ reliable and valid?

•227 nuclear transfers led to 29 embryos implanted in 13 ewes of which 1 succeeded

Courtesy of Advanced cell technology at http://science.howstuffworks.com/cloning.htm

“On January 8, 2001, scientists at Advanced Cell Technology, Inc.,

announced the birth of the first clone of an endangered animal, a baby bull gaur (a large wild ox from India and southeast

Asia) named Noah. Noah died of an infection unrelated to the procedure. “


Cloning to save endangered species?

•How can scientists guarantee that Noah’s immune system was not compromised by his being a clone? His unusual genetics may have affected the function of immunological proteins reducing his chance of survival.

•Is this worthwhile & ethical?


Cloning to replace a family pet?

http://www.mun.ca/biology/scarr/Cloned_Cat.htm

Cloned cat

Clone (CC)

Surrogate mother with CC

•Cloning solely for ‘emotional’ reasons – is it worthwhile and ethical?

•Are owners really ‘replacing’ a loved pet?

•Should money be spent on cloning for these reasons?

•We also need to consider the sensationalist press regarding the cloning of humans…

“The 6th cloned baby was born on Thursday the 5th of February [2003] in Australia.The Clonaid team, after 20 more implantations, had 8 successful pregnancies. The first one of

this new series is now born, perfectly healthy and his health is documented today by a pediatrician in Sydney.The seven other babies are expected these two coming weeks. An update will be made for each birth on this website. nb: The cloned child

born in Australia was not conceived within Australia and therefore adheres to Australian cloning laws.”h

ttp:/

/ww

w.c

l onai d

.com

/new

s.php


Cloning humans?

•Clonaid – fact or fallacy?

•Australian experts (such as Alan Trounson) say ‘fallacy’.

4. Therapeutic Cloning of animal undifferentiated embryonic stem (ES)

cells derived from SCNT for tissue repair

“Reproductive cloning to produce human fetuses is unethical and unsafe and should be

prohibited. However, human cells, whether derived from cloning techniques or from

embryonic stem cells should not be precluded from use in approved research activities in

cellular and developmental biology.”

The Australian Academy of Science (1999) had this to say on Human Cloning:

4. Therapeutic Cloning of animal undifferentiated ES cells derived from SCNT

for tissue repair•Therapeutic cloning follows the same steps as reproductive cloning until the point where the embryonic stem cell is implanted into a surrogate female.

•Therapeutic cloning means that an oocyte is enucleated, and fused with the nucleus from a somatic cell. This undifferentiated embryonic stem cell is then cloned by being allowed to undergo mitosis. Before the cells start to differentiate and program themselves to specific roles, scientists can grow them into the cell types they desire, such as nerve cells, skin cells or myocardial (heart muscle) cells.

•In humans, embryonic stem cells are cultured in the laboratory and grown into specialised tissue. such as skin cells for grafting. Professor Alan Trounson from Melbourne is Australia’s leading stem cell researcher.

•Skin cells can be grown and used for skin grafts, nerve cells used to treat neurological disorders such as Parkinsons or Altzeimers, and miocardial cells used to treat patients with heart muscle disorders.

•The grafted tissue is immunologically compatible as it is the patients own.

4. Therapeutic Cloning of animal undifferentiated ES cells derived from SCNT

for tissue repair

Reproductive cloning

htt

p:/

/sci

ence

.how

stuff

work

s.co

m

Embryonic Stem cells

cultured in a petrie dish

Eg. Stem cells used to grow skin cells for

grafting

•Advanced cell technology in 2001 (USA) have already reported human cloning for therapeutic reasons.

•Is therapeutic cloning ethical?

•Is the embryo alive?

•Does the embryo have a right to survive?

•More efficient and cheaper ways to mass produce good quality food and clothing supplies

•Endangered species could be cloned to increase their population.

•Extinct species could be brought back to life.

•Human body parts can be harvested and cloned by therapeutic cloning.

Cloning – arguments for

•Cloning will reduce differences in the genetic make-up within the different species so uniqueness and individuality in individuals would disappear.

•If all species have identical genetic material, a disease could wipe out the entire population of the particular species.

•Cloning certain animals will over produce them and then under produce others reducing biodiversity.

•Corporate greed will take over as companies try to market organisms and/or genes

•Nuclear transfer has a high failure rate.

•We are taking nature into our own hands i.e. we are trying to play God.

•If the technology falls into the wrong hands the effect could be disastrous. Extremist groups could make the so-called “supper race”

•Cloning body parts actually creates something alive, so do these body parts have rights?

Cloning – arguments against

Cloning – more contentious reasons (mostly human cloning)

•Offspring can be born without a father.

•We could bring back relatives, loved ones and famous people.

•Parents who can’t have children physically can clone to produce their own offspring.

•Parents can ‘replace’ a dead child (are they really replacing them?)

•Families with diseases could clone healthiest parent

Transgenic Species

•A transgenic organism is one that has a gene from another organism inserted into its own genetic material. This is also known as DNA recombination.

•If one organism doesn’t have a particular characteristic then scientists find and isolate a gene from another organism that does code for that characteristic and then insert it into the original organism.

•Genes can be added by:

•Micro-injecting into embryonic stem cells

•Using electrical pulses (electroporation)

•Injecting using a gene gun

•Transferring using a bacteria or virus

Transgenic Species – using bacteriaBacterial Chromosome

Bacterial plasmid

(enlarged)

Section of DNA from source is cut out using restriction enzymes

The bacterial plasmid is also cut with the restriction enzyme and the source DNA is inserted

Host organism is infected with the bacteria whose DNA incorporates into the hosts chromosome

Transgenic Species•For example a bacteria called Bacillus thuringiensis (Bt) can make a protein that is toxic to insects. Scientists have managed to take the gene that codes for this protein – the Bt gene - and insert it into crops such as wheat and soy. The crops are then immune to the insects that might eat it.

•GM foods examples: herbicide resistant corn, antifreeze from cold-water fish into strawberries, vaccine in bananas, tomatoes with a longer shelf life.

•In mammals, SCNT derived ES cells can be genetically altered by DNA recombination (in this case inserting a novel gene) and then transplanted into a surrogate mother. Transgenic sheep have been produced that secrete a protein (antitrypsin) in their milk that helps treat human lung disease.

•Other milk producing mammals can produce factor VIII to help hemophiliac’s blood clot and insulin for diabetes sufferers.

•Transgenic mice (rats, rabbits) have been genetically engineered with human diseases in order to help scientists find a cure for that disease.

Transgenic Species – arguments against

•Genetically engineered organisms might hybridize with natural organisms and produce new diseases, or resistance to certain drugs

•Bacteria or viruses used to transfer genes from one organism to another could become harmful and spread throughout the population

•Eating GE food could affect health – ie allergies sufferers, animals virus passed on to humans

•Religious diets

•Endangered insects could eat Bt crops and die

•The health of the transgenic organism might be at risk (transgenic pigs have arthritis)

•Eugenics movements might resurface

•Corporate greed will take over as companies try to market organisms and/or genes. Terminator seed – disease resistant and produce bumper crops but cannot be harvested. Monsanto have the patent.

•Transgenes might ‘escape’ into native populations and disrupt the ecosystem

•In the long term transgenic organisms will be cloned, reducing genetic variation

Transgenic Species – arguments for

•Improve livestock and agricultural products for human use. This includes improving productivity, quality and ability to live in extreme conditions.

•Improve the resistance of plants and animals to diseases or chemicals such as herbicides .

•Organisms that can genetically fight off predators means there is less harmful spraying of poisonous chemicals into the environment.

•Disease and human defects could be reduced.

•New products can be developed, such as medicines and vaccines.

•People living in developing countries can be given food with enhanced nutrient content to reduce disease due to deficiencies.

•Vaccines can be eaten thus reducing the cost of production.

•In the short term genetic diversity is increased.

Maintaining Biodiversity - recap

•Over production of one organism reduces the number of different genes in a population which can create a problem if the environmental conditions change either physically or chemically.

•Over production of one species of potato in Ireland led to reduced biodiversity with deadly consequences for the population (in South America they had hundreds of species).

•The healthy function of natural ecosystems relies on biodiversity.

•Research on different varieties of plants can provide new medicines.

•Seed banks have now been set up in order to safeguard different varieties of plants.

•Habitat conservation to stop the destruction of diverse species.

The End?

“This is not the end. It is not even the beginning of

the end. But it is, perhaps, the end of the

beginning.”Winston Churchill

References•Allan, R. (2000) Year 12 Biology 2001 – Student Resource and Activity Manual BIOZONE, International Ltd.

•Aubusson, P. and Kennedy, E. (2000) Biology in Context. The Spectrum of Life Oxford University Press, Melbourne, Australia.

•Australian Academy of Science (1999) Therapeutic Cloning for Tissue Repair

•Biever, C. [2003] New Scientist Online: UN postpones global human cloning ban Retrieved from site http://www.newscientist.com/hottopics/cloning/cloning.jsp?id=ns99994359 April 2004.

•Board of Studies (2002) STAGE 6 SYLLABUS Biology Board of Studies, NSW, Australia.

•Clonaide;Pioneers in Human Cloning [no date] Retrieved from the site http://www.clonaid.com/news.php April 2004.,

•Equiworld magazine [no date] Retrieved from the site http://www.equiworld.net/uk/horsecare/artificialinsemination/artificialinsemination.htm April 2004.•Freudenrich, C [no date] How Cloning Works Retrieved from site http://science.howstuffworks.com/cloning.htm April 2004.•Hamilton Research (2003) The Equicontainer retrieved from the site http://www.equitainer.com/ April 2004.

References

•Humphreys, Kerri (2003) Biology. Blueprint of Life. Science Press, Australia.

•Issues in Society: Cloning (1999) Ed. Justin Healey, The Spinney Press, Australia.

•Kinnear, J and Martin, M (2001) Biology 2 HSC Course: Jacaranda HSC Science John Wiley & Sons, Australia, Ltd.

•Mudie, K. et.al. (2000) Heinemann Biology Malcom Parsons, National Library of Australia, Australia.•Schwartz, Shaul (2004) Corbis. Retrieved from the site http://pro.corbis.com/search/searchFrame.asp April 2004.•Sneddon, R (2002) DNA & GENETIC ENGINEERING Reed Educational and Professional Publishing Ltd Heinemann, Oxford, UK. •[author not known] [no date] Rainbow and cc, the world’s first cloned cat Retrieved from site http://www.mun.ca/biology/scarr/Cloned_Cat.htm April 2004.•Wilmut, I. et.al. (2003) Human Cloning: Can it be made safe? Nature Reviews.Genetics. Vol 4 November.

CLONAIDTM, the first human cloning company in the world, was founded in February 1997, by RAËL and a group of investors who created the Valiant Venture Ltd Corporation based in the Bahamas. In the first couple of years CLONAID™ has already

received enormous media coverage. However, due to the pressure mounted on the Bahamas government by French

journalists, Valiant Venture Ltd was cancelled as government representatives were thinking the laboratories would be

established on the Bahamas Island. Meanwhile, the list of serious potential customers had grown to more than 250

people! Therefore, during the year 2000, Rael decided to hand over the CLONAID™ project to Dr. Brigitte Boisselier, a Raelian Bishop, in order for her to start working on actually cloning the

first human being with a team of well-trained scientists. Dr. Boisselier has PhD degrees in physical and biomolecular

chemistry. In her last job she was a marketing director for a large chemical company in France.

http://www.clonaid.com/news.php


htt

p: /

/ww

w.c

l onaid

.com

/new

s .php


CLONAID™: New cloning services• If you are a sterile couple with no more hope of having the child you dream of,• If you are a homosexual couple with a profound desire to have a child carrying your own genes, • If you are infected with the HIV virus and you would like to have a child carrying your own genes without passing on the virus to the baby nor to your partner, • If you just lost a beloved family member and would like to see an identical twin of him/her live again, • If you want to be cloned, whatever your reasons may be, then CLONAID™ has the right program for you.

•Are these ‘reasons’ for cloning humans justifiable?

•The need for governments to have specific laws to keep pace with advancing biotechnology – particular human cloning - is essential.

Nuclear transfer

UN postpones global human cloning ban

“The United Nations' General Assembly in New York narrowly voted to postpone any ban on human cloning until 2005 on Thursday, leading many scientists around the world to breathe a sigh of relief.Reproductive cloning - creating babies - is regarded by virtually everyone as dangerous and unethical. But opinion is split on therapeutic cloning - the use of cloned embryos to harvest stem cells for medical use. Supporters say the approach offers unrivalled promise for the treatment of many diseases, such as Parkinson's and diabetes. "No decision is better than the wrong decision," says Bob Ward, spokesperson for the UK's premier scientific association, the Royal Society. Ian Wilmut, who led the cloning of the first adult mammal, Dolly the sheep, agrees: "I think it is a lesser evil to have this solution than to have a complete ban…I am convinced that therapeutic cloning offers health opportunities that you could not attain in any other way,"

http

://ww

w.n

ew

scientist.co

m/h

otto

pics/clo

nin

g/clo

nin

g.jsp

?id=

ns9

99

94

35

9


Already banned in 30 countries

Documents

Altering the Path of Evolution Current Reproductive Technologies and Genetic Engineering with the use of